A shark expert makes the determination after examining the body of Francisco Javier Solorio Jr. and the board he was using at a beach near Vandenberg Air Force Base.

LOMPOC — The shark that attacked a surfer at Surf Beach was a great white, estimated at 15 to 16 feet in length, according to the Santa Barbara County sheriff.

Ralph S. Collier, a shark expert from the Shark Research Committee of Chatsworth, made the determination Wednesday after examining the body of Francisco Javier Solorio Jr. and the board he was using when the shark attacked, according to a statement from the sheriff's office.

Collier said he estimated the size of the shark based on the distance between teeth marks on the board.

Solorio, 39, suffered a massive wound to the torso in the Tuesday attack. A fellow surfer brought him ashore, where he died despite efforts to revive him.

The beaches at Vandenberg Air Force Base remain under a 72-hour closure.

"The intent is to allow time for any potential hazard to leave the area," said Col. Nina Armagno, 30th Space Wing commander at the base. "Officials from Vandenberg and Santa Barbara County are working together to reopen our beaches."

A locked gate greeted anyone daring — some would say foolish — enough to enter the waters off Surf Beach so soon after the death of a surfer at the windy, dune-fringed spot five miles from Lompoc.

"It's Surf Beach and, ironically, we're advising people not to surf it," said Sherwin Gunn, an employee at Surf Connection, a Lompoc shop that offers gear for skateboarders and surfers.

Gunn echoed other locals about the downsides of Surf Beach. The currents are tricky, they say, and the ride, even for experienced surfers, is choppy, measured in powerful bursts instead of long, swooping arcs.

"Nobody local looks at it like a nice day at the beach," Gunn said.

Solorio was an avid surfer who had frequented the spot since he was a boy. He is survived by his wife and their young daughter.

The day before Solorio's death, the family of Lucas Ransom, a 19-year-old chemical engineering student at UC Santa Barbara, gathered at Surf Beach in his memory. He was killed by a shark on Oct. 22, 2010. They also paid tribute to Ransom, who would have graduated from the university last June, by establishing a scholarship in his honor.